Abstract: The coatings are glass compositions which consist essentially of from 18 to 45 mol % of the alkaline oxides CaO and one or both of Na.sub.2 O and K.sub.2 O and from 5 to 22 mol % of Al.sub.2 O.sub.3, the balance being B.sub.2 O.sub.3 and SiO.sub.2 in such amounts that the molar ratio of B.sub.2 O.sub.3 : (B.sub.2 O.sub.3 +SiO.sub.2) lies in the range from 0.575:1 to 0.85:1. The molar ratio of K.sub.2 O: (K.sub.2 O+Na.sub.2 O) is from 0.4:1 to 0.6:1 and CaO is 48 to 52 mole % of the alkaline oxides.These compositions are particularly suitable for use during the heat-treatment and hot-working of titanium and its alloys.

Abstract: A method for producing aluminum rings without developing undesirable residual stresses. A hot ring blank is ring rolled to a diametric size ranging approximately between 1% and 3% smaller than the desired dimensions of the finished ring. The ring is subsequently heated, quenched, subjected to cold ring working, and then aged prior to final machining.